@scoped-vaadin/grid/src/lit/renderer-directives.js

A free, flexible and high-quality Web Component for showing large amounts of tabular data

/**
 * @license
 * Copyright (c) 2017 - 2024 Vaadin Ltd.
 * This program is available under Apache License Version 2.0, available at https://vaadin.com/license/
 */
import { directive } from 'lit/directive.js';
import { microTask } from '@scoped-vaadin/component-base/src/async.js';
import { Debouncer } from '@scoped-vaadin/component-base/src/debounce.js';
import { LitRendererDirective } from '@scoped-vaadin/lit-renderer';

export const CONTENT_UPDATE_DEBOUNCER = Symbol('contentUpdateDebouncer');

export class GridRowDetailsRendererDirective extends LitRendererDirective {
  /**
   * Adds the row details renderer callback to the grid.
   */
  addRenderer() {
    this.element.rowDetailsRenderer = (root, grid, model) => {
      this.renderRenderer(root, model.item, model, grid);
    };
  }

  /**
   * Runs the row details renderer callback on the grid.
   */
  runRenderer() {
    this.element[CONTENT_UPDATE_DEBOUNCER] = Debouncer.debounce(
      this.element[CONTENT_UPDATE_DEBOUNCER],
      microTask,
      () => {
        this.element.requestContentUpdate();
      },
    );
  }

  /**
   * Removes the row details renderer callback from the grid.
   */
  removeRenderer() {
    this.element.rowDetailsRenderer = null;
  }
}

/**
 * A Lit directive for rendering the content of the row details cell.
 *
 * The directive accepts a renderer callback returning a Lit template and assigns it to the grid
 * via the `rowDetailsRenderer` property. The renderer is called for each grid item that is in `detailsOpened`
 * when assigned and whenever a single dependency or an array of dependencies changes.
 * It is not guaranteed that the renderer will be called immediately (synchronously) in both cases.
 *
 * Dependencies can be a single value or an array of values.
 * Values are checked against previous values with strict equality (`===`),
 * so the check won't detect nested property changes inside objects or arrays.
 * When dependencies are provided as an array, each item is checked against the previous value
 * at the same index with strict equality. Nested arrays are also checked only by strict
 * equality.
 *
 * Example of usage:
 * ```js
 * `<vaadin24-grid
 *   ${gridRowDetailsRenderer((item, model, grid) => html`...`)}
 * ></vaadin24-grid>`
 * ```
 *
 * @param renderer the renderer callback.
 * @param dependencies a single dependency or an array of dependencies
 *                     which trigger a re-render when changed.
 */
export const gridRowDetailsRenderer = directive(GridRowDetailsRendererDirective);